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241.
复杂成形装备作为高端制造产业的基础装备,是各产业转型升级和技术进步的重要保障。同时快速发展的互联网与大数据等新兴信息技术已经成为装备制造业创新不可或缺的组成部分,极其深刻地影响着复杂成形装备产业的制造模式、发展战略以及产品的开发方式。本文研究了面向服务的复杂成形装备产品架构设计与优化方法。采用公理化设计的域结构思想,建立需求域、功能域和架构域之间的映射关系;提出了基于QFD的功能生成方法以及功能模型约简方法;利用DMM建立产品架构和服务架构之间的关联关系;利用模块化理论方法,并考虑成本因素对产品架构进行优化。  相似文献   
242.
The concept of transparency has been promoted within the public relations and business literature as both ethical and advantageous; however, the effectiveness of transparency is seldom empirically put to the test. In particular, the use of clarity, disclosure, and accuracy in organizational messages needs to be empirically examined. To this end, we conducted an online experiment using a 2 (high vs. low message transparency) x 2 (news story placed before or after an organizational statement) between-subjects design. Participants (n?=?357) perceived organizations as more transparent and credible when exposed to messages exhibiting greater levels of clarity, disclosure, and accuracy as opposed to messages that did not. Placement of an information anchor in the form of an objective news story before the organizational message increased the perceived organizational transparency when messages employed transparent design features and decreased the perceived organizational transparency when messages did not use these features. These results provide significant implications for practitioners attempting to convey organizational transparency at the tactical level through message features.  相似文献   
243.
abstract

Despite the attention given to universal design in recent years, many people with impairments still refrain from travelling on public transport. This explorative case study, conducted in the greater Oslo region in Norway, aims to add knowledge on why this is so. Findings indicate that insecurity while travelling and expectations of problems along the way are significant barriers. For many it is the sum of all challenges combined, from experience or anticipation that leads to non-use of public transport. The study shows that universal design policy, as of today, does not lead to accessible public transport systems that rendered impairments irrelevant. If society could safeguard the individuals’ travel needs, this might have profound societal repercussions through increased workforce participation and value added in society. Only then can society make the best use of all its inhabitants while championing inclusiveness and equality.  相似文献   
244.
自三代始,迄于近代,上下四千年。其间,制度设计之事,史不绝书。然而,择其具有原创意义、影响中国历史进程的制度设计,主要有三次,分别出现在周代、秦朝和近代。在中国文化语境中,古代制度设计权属于王和圣,虽为价值有涉,但也使“天下为家”体现出“天下为公”的理想。前两次制度设计以家天下政治为核心,先后形成了王制和帝制的模式;近代以孙中山为首的民族资产阶级的制度设计,效仿法、美模式,开启中国民主制度的先河,奠定了中国政治的基本方向。从历史背景、设计者及思想来源、系统性、创新性、本质性和对外影响来比较,三次制度设计既有相同性也存在着本质差别。三次制度设计对中国历史的进程有重要影响,可以作为中国历史上时代划分的标志。三次制度设计皆发生在中国历史转折时期,其影响之深远,意义之重大,留下了宝贵的历史经验、启示和借鉴。  相似文献   
245.
Summary.  We propose covariance-regularized regression, a family of methods for prediction in high dimensional settings that uses a shrunken estimate of the inverse covariance matrix of the features to achieve superior prediction. An estimate of the inverse covariance matrix is obtained by maximizing the log-likelihood of the data, under a multivariate normal model, subject to a penalty; it is then used to estimate coefficients for the regression of the response onto the features. We show that ridge regression, the lasso and the elastic net are special cases of covariance-regularized regression, and we demonstrate that certain previously unexplored forms of covariance-regularized regression can outperform existing methods in a range of situations. The covariance-regularized regression framework is extended to generalized linear models and linear discriminant analysis, and is used to analyse gene expression data sets with multiple class and survival outcomes.  相似文献   
246.
On pseudo-values for regression analysis in competing risks models   总被引:2,自引:2,他引:0  
For regression on state and transition probabilities in multi-state models Andersen et al. (Biometrika 90:15–27, 2003) propose a technique based on jackknife pseudo-values. In this article we analyze the pseudo-values suggested for competing risks models and prove some conjectures regarding their asymptotics (Klein and Andersen, Biometrics 61:223–229, 2005). The key is a second order von Mises expansion of the Aalen-Johansen estimator which yields an appropriate representation of the pseudo-values. The method is illustrated with data from a clinical study on total joint replacement. In the application we consider for comparison the estimates obtained with the Fine and Gray approach (J Am Stat Assoc 94:496–509, 1999) and also time-dependent solutions of pseudo-value regression equations.  相似文献   
247.
Two-stage designs offer substantial advantages for early phase II studies. The interim analysis following the first stage allows the study to be stopped for futility, or more positively, it might lead to early progression to the trials needed for late phase II and phase III. If the study is to continue to its second stage, then there is an opportunity for a revision of the total sample size. Two-stage designs have been implemented widely in oncology studies in which there is a single treatment arm and patient responses are binary. In this paper the case of two-arm comparative studies in which responses are quantitative is considered. This setting is common in therapeutic areas other than oncology. It will be assumed that observations are normally distributed, but that there is some doubt concerning their standard deviation, motivating the need for sample size review. The work reported has been motivated by a study in diabetic neuropathic pain, and the development of the design for that trial is described in detail.  相似文献   
248.
论“跨文化交际”课程设计模块化   总被引:1,自引:0,他引:1  
利用美国学者陈国明先生的跨文化交际能力的模型,结合跨文化课程设计理论和国内研究数据,完成课程概念性的模块化设计,为国内同行提供一个课程设计的新思路。  相似文献   
249.
地震灾害给人类社会生活带来重大影响。加强建筑工程质量管理,防止地震灾害,成为备受社会关注的热点问题。要从提高全民质量意识入手,建立健全有效的质量监督机制、提高建筑设计质量,加强施工质量控制.为人民安居乐业创造良好的环境。  相似文献   
250.
Most studies of quality improvement deal with ordered categorical data from industrial experiments. Accounting for the ordering of such data plays an important role in effectively determining the optimal factor level of combination. This paper utilizes the correspondence analysis to develop a procedure to improve the ordered categorical response in a multifactor state system based on Taguchi's statistic. Users may find the proposed procedure in this paper to be attractive because we suggest a simple and also popular statistical tool for graphically identifying the really important factors and determining the levels to improve process quality. A case study for optimizing the polysilicon deposition process in a very large-scale integrated circuit is provided to demonstrate the effectiveness of the proposed procedure.  相似文献   
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